Spindle brake with articulated and detachable brake shoes

ABSTRACT

A manually actuable brake for rotatable spindles of textile yarn processing machines is disclosed wherein the bifurcate branches of the elastically deformable brake have at their leading separated ends joined or articulated brake shoes which are pivotable and detachable at their pivot joints from said branches for, respectively, application of full braking surfaces to the spindle upon initial contact and ready replacement of the shoes when they become worn and no longer functional.

United States Patent [191 Preston et al.

[4 1 May 7,1974

SPINDLE BRAKE WITH ARTICULATED AND DETACHABLE BRAKE SHOES Inventors: Frederick AJPreston, Pendleton;

Philip B. Tarbox; Gordon C. Anderson, both of Clemson, all of S.C.

Saco-Lowell Corporation, Easley, S.C.

Filed: July 23, 1973 Appl. No.: 381,638

Assignee:

U.S. Cl. 57/88 Int. Cl D0lh 7/22 Field of Search 57/34 R, 129, 88, 130;

References Cited UNITED STATES PATENTS 3/1964 Swift et al 57/88 3,226,923 1/1966 Maurer 57/88 3,406,512 10/1968 Stahlecker v 57/88 3,681,908 8/1972 Hohloch 57/88 2,449,773 9/1948 Hargreaves et al. 57/88 UX Primary Examiner-Donald E. Watkins Attorney, Agent, or Firm-Donald H. Feldman [57] ABSTRACT 8 Claims, 8 Drawing Figures Pmmeuw 11914 3.898790 SHLEI 3 OF 5 PATENTEDHAY 7 m4 SHEET 5 [IF 5 SPINDLE BRAKE WITH ARTICULATED AND DETACHABLE BRAKE SHOES BACKGROUND OF THE INVENTION This invention relates to manually actuable and deactuable brakes for spindles of textile yarn spinning and twister machines. Particularly, it relates to brakes having a braking arm vertically pivotable relative its respective spindle and having bifurcate branches for embracing therebetween a rotatable member of the spindle to effect braking thereof, said branches being eleastically deformable relative one another, and most particularly to such an elastically deformable, bifurcate branched brake wherein each branch has at its leading edge an articulated, pivotable and separable or detachable brake shoe to effect said braking.

Somewhat similar brakes of the foregoing type, devoid however of the present articulated brake shoes, have been known in the art, such as that of-Maurer as disclosed in his US. Pat. No. 3,226,923 and that of Zinser Textilmaschinen GmbH as disclosed in its British Pat. specification No. 1,281,806. The Maurer brake is essentially of one piece, formed integrally of an elastically deformable structural plastic material and having a brake shoe, wear resistant material lining the interior spindle confronting surfaces of the arcuate periphery of the bifurcate branches for contact with and braking of a rotating spindle; the Zinser brake is formed essentially of three parts, a left-hand branch and handle portion, a right-hand branch and handle portion, and an elastically deformable joining portion which latter holds together the right and left hand portions so that they are eleastically deformable relative one another, such as in the form of a leaf spring; the Zinser brake also has a brake shoe material lining the interior confronting surfaces of the right and left branches.

The advantages obtained by spindle brakes of these prior art constructions are substantial and include not only great simplicity of design, construction and operation, but also very low cost due to economical manufacture of such brakes from inexpensive materials and relatively few components. The value of the foregoing will be readily understood when one considers that a textile mill commonly employs several thousand spindles, each requiring abrake. Thus, use of so inexpensive a brake can be expected to provide the mill user with great economies over use of brakes hitherto known.

Although initial purchase of the several thousand brakes can be much lower than that of other types of I spindle brakes, another consideration must be taken into account, that of the useful lifetime of such a brake before replacement is required, that is to say the durability of such a brake, and the replacement costs attendant thereto.

We have observed that, in normal mill operation, such brakes of Maurer or Zinser have a useful lifetime of between 6 months and two years, and once worn and no longer capable of a self-holding on the spindle member must be replaced in their entirety. Thus, a mill may expect to replace all such prior art brakes with new brakes every 2 years, the replacement costs being as great as the initial costs. As mentioned, since these brakes number in the thousands such replacement costs every 2 years can be substantial.

The reason why these prior art brakes have so short a useful lifetime, and why they must be replaced in their entirety can best be understood from a knowledge of how they wear. We have observed that substantially all wear due to repeated brakings is concentrated or localized at and near the interior confronting peripheries of the branches at and near their leading or outer edges. When the brake is pivoted into contact with a rotating member of the spindle, it is the leading edges which first make contact and upon such contact stop rotation of the spindle. Thus it is there where abrasion takes place and consequent wear. When the brake is new, the distance between the interior confronting or opposing leading edges of the branches is less than the diameter of the spindle member which they embrace. Once the edges make contact and spindle rotation is stopped, a further pivoting of the brake toward the spindle causes these edges to snap over the spindle member elastically deforming the brake so as to hold the brake on the member in an elastic embrace, thus freeing both hands of the operator for repairing yarn breakages, rethreading yarn guides and the traveler, which latter are the usual reasons for stopping the spindle. However, after repeated applications of the brake such repeated abrasions will remove all of the brake shoe material thereat. The material underlying the brake shoe material at these edges usually is not particularly wear resistant, and thus will quickly wear away upon subsequent applications of the brake, ultimately to provide a separation distance of the branches at these now worn leading edges which is greater than the diameter of the spindle member. At this time, the brake will no longer be capable of holding itself on the spindle member; further use of the brake then would require manual holding of the brake against the spindle member, which is completely impractical, since the operator requires both hands free to perform the aforesaid repair and rethreading operations.

When the prior art brake has become .worn it must be replaced in its entirety because there is no way of replacing merely the brake shoe material.

OBJECTS OF THE INVENTION Therefore, it is an object of this invention to provide an elastically deformable, manually pivotable bifurcate branched spindle brake which has replaceable brake shoes and an indefinite useful life.

,Another object is to provide such a brake wherein its replaceable brake shoes are articulatedly and pivotally joined to the branches of the brake so that upon first contact of the shoes with a rotating member of the spindle such contact is made'along the full braking surfaces of the shoes, rather than at a point as in the brakes of the prior art.

A further object of the invention is to provide such a bifurcate branched brake wherein the branches are separated by a distance greater than the diameter of the spindle member which they embrace, thus to obviate abrasive wear of the branches.

Yet further desirable objects and advantages of the invention will become apparent from or are inherent in the descriptions thereof which follow.

SUMMARY OF THE INVENTION In view of our observations, as abovementioned, we have discovered that substantial economies are realizable when a spindle brake is provided with replaceable brake shoes. To this end we have invented an elastically deformable, bifurcate branched brake for textile spindles which is pivotally attachable and detachable from spindle assemblies, in similar manner to those described in aforesaid U.S. Pat. No. 3,226,923 and British Pat. specification No. 1,281,806, which is fitted with pivotable, attachable and detachable brake shoes at the leading ends of the branches thereof which embrace a rotatable spindle member for the braking thereof. The distance between the the branches, according to the invention, may be less than, equal to or greater than the diameter of the spindle member which they embrace; in its most preferred embodiment, to realize the advantages of obviating any wear on the branches, the distance therebetween is greater than the said diameter; the brake shoes are attached to the respective branches to which they are pivotally joined such that they extend beyond the peripheries of the branches so that the distance along the line between the pivot points which extends between the braking surfaces of the shoes is less than said diameter. Means for providing detachable pivotal interconnection between the shoes and their respective branches may be in the form of pivot pins which are removable and replacable, or in the form of a ball and socket joint with one of each molded or formed as a part of the shoe and the other as a part of the corresponding branch, in the preferred embodiments.

DRAWINGS A fuller understanding of the nature of the present invention and its mode of operation and usagemay be had through the following descriptions and explanations when taken in conjunction with the appended drawings in which:

FIG. 1, a perspective view in fragmentary side elevation and partially in section, shows a typical spindle assembly having attached thereto a brake of the invention in its braking or actuated position, the brake shoes thereof being pin-linked or articulated with the branches for pivotal movement;

FIG. 2, a perspective view in fragmentary front elevation, is otherwise similar to FIG. 1 but shows the brake in a released or deactuated position;

FIG. 3, in sectional plan view taken generally along line 3-3 of FIG. 1, shows the brake actuated, the relative separations of the brake shoes and the branches along the line joining the pivot points of the, brake shoes, and the relative positioning of said line relative a parallel diameter of the spindle member which the brake branches embrace;

FIG. 4 is a sectional plan view taken generally along line 44 of FIG. 2, showing in detail the present brake shoes and their braking surfaces and their recessed pivotal joining to the brake branches;

FIG. 5 is a fragmentary front elevational view of the brake with itsarticulated shoes making initial and full contactwith the spindle member prior to achieving the actuated position as shown in FIGS. 1 and 3;

FIG. 6 is a plan view in partial section taken generally along line 6-6 of FIG. 5 but showing the brake being released and its articulated shoes making last contact with the spindle member prior to full release as shown in FIGS. 2 and 4;

FIG. 7 is a fragmentary plan view partially in section of another embodiment ofthe present brake wherein the brake shoe is pivotally joined to the respective branch by means of a ball and socket joint; and

FIG. 8 is a fragmentary sectional view of the ball and socket joint taken generally along line 88 of FIG. 7.

PREFERRED EMBODIMENTS One embodiment of the present brake employing a detachable pivot pin joining the brake shoe with its respective branch may best be seen by reference to FIGS. 1 to 6. a

A typical spindle assembly commonly employed in yarn spinning or twister machines is shown in FIGS. 1 and 2. Therein, spindle assembly 10 comprises an upstanding spindle blade or shaft 12 for receiving thereonto a tube onto which yarn is spun or twisted, a driving whirl l4 for'receiving thereabout a driving belt (not shown) which rotates blade 12, whirl 14 having an upper flange l6 and a lower flange 18 to retain therebetween the driving belt, lower flange 18 also serving as the rotatable spindle member which is received between or embraced by the branches of the present brake when the latter is actuated.

A brake of the invention, generally designated 20, is

shown to comprise a brake arm 22 having bifurcate branches 23 and 23', a handle 24 formed integrally with arm 22 and extending outwardly therefrom at an upwardly directed angle thereto, and downwardly directed pivot arms 26 and 26 formed integrally with branches 23 and 23' having inwardly directed pivot pins (not specifically numbered) for pivotal connection of brake 20 with a fixed member of assembly 10 such as spindle mounting ring 28 into recesses therein. In order to mount brake 20 onto assembly 10, branches 23 and 23' are forced apart elastically deforming brake 20 a distance sufficient for the pivot pins of arms 26 and 26' to enter and be retained by the recesses in ring 28, whereupon the force of separation is removed, brake 20 elastically recovers and is held onto assembly 10 for vertical pivoting thereabout between a position of brake engagement with assembly) and one of release ordisengagement as shall later be described. In similar manner, brake 20 may be detached from assembly l0. Alternately, ring 28 may have the pivot pins,

and arms 26 and 26' may be formed with the recesses I to receive such pins. In order that assembly 10 be held in proper position on the ring rail 30 of the textile machine (not otherwise shown), spindle assembly 10 has a downwardly extending fixed screw member 32 for receiving a lock nut 34, assembly 10 then being rigidly held on rail 30 by ring 28 and nut 34. All of the foregoing is known from the descriptions of Maurer in U.S. Pat. No. 3,226,923.

Unlike the prior art, however, present branches 23 and 23' are formed with brake shoe receiving recesses 36 and 36', respectively to receive and hold the brake shoes of the invention 38 and 38' therewithin, such that shoes 38 and 38' may be pivotally joined to branches 23 and 23. Such joining is effected in this embodiment by means of the pivot pins 40 and 40' passing through branches 23 and 23 and respective shoes 36 and 36 near the outer ends thereof at pivot points located on line PC therebetween (see FIG. 3, especially). It also will be noted that the separation of branches 23 and 23 is such that the distance along line PC between opposing faces of the branches is greater than the diameter of whirl flange 18 so that no contact between these branches and the whirl flange can occur obviating abrasive wear. of the former; also to be noted is that the distance between the braking faces of shoes 36 and 36' along line PC is such that it is always less than or equal to the diameter distance of whirl flange 18, less than such diameter when the shoes have not as yet been worn to a state of inoperativeness and equal to said diameter when the shoes have been worn to such state and require replacement. Yet further, it is to be noted that when brake is in its actuated and holding position the pivot point line PC and pivot points and 40' have been moved beyond the parallel diameter line SC of flange l8 and, in effect, brake branches 23 and 23' and shoes 38 and 38 have been snapped over center of spindle assembly 10. Referring to FIG. 3, although some separation is shown between the confronting surface 18 of flange 18 and the rear confronting surface 22' of brake arm 22 at the apex of branches 23 and 23', and thus the brake most technically is not as yet in its holding position, such separation was made for purposes of clarity of illustration only, the purpose of such abutment between surfaces 18 and 22' being dicussed below. Further, according to the invention, shoes 38 and 38' are formed of a wear resistant brake lining material with an arcuate brake face or surface for confronting and of complementary arcuity to that of the rotatable spindle member, and in this embodiment to that of whirl flange 18. The pivotable-point of attachment of shoes 38 and 38' with the respective branches is located such that upon contact of shoes 38 and 38' with flange 18, shoes 38 and 38' will pivot until the full braking surfaces of these shoes conform to the complementary arcuity of flange 18; yet further slight additional upward force on handle 24, with such braking surfaces in full contact, applies the braking surfaces to the flanges rotating surface and stops flange 18 and fixedly attached spindle blade 12.

Thus, in operation, a raising of handle 24 stops spindle rotation by application of the full braking surfaces of shoes 38 and 38' against flange l8, and a still further raising of handle24 moves shoes 38 and 38' over the now stopped surface of flange 18 until pivot points 40 and 40 and line PC therebetween are beyond the parallel center line SC of assembly 10. Once achieved, brake 20 is in a holding position and shall retain such holding position until handle 24 is lowered. In order that the holding position of shoes 38 and 38 be made consistent from one application of brake 20 to the next application of brake 20, we have provided holding means, in this embodiment in the form of cooperating abutment surfaces 18' on the whirl flange and 22 on the opposing or confronting surface thereto of brake arm 22. With the spindle thus stopped, and brake 20 in a holding and engaged position thereon, the operator with both hands now free may pursue activities for which purpose the spindle was stopped. Once such activities have been completed, the operator moves the handle downward, and in so doing moves surface 22 out of abutment with flange surface 18', moves shoes 38 and 38' rearward on non-rotating flange 18 until they are completely out of engagement with its surface, and when so released spindle blade 12 is once again free to rotate under the force of the driving belt about whirl 14; during the period when the brake is applied and blade 12 is stopped, the driving belt merely slips over the surface of stopped whirl 14.

Another embodiment is shown in FIGS. 7 and 8 wherein the pivot points are shown in the form of ball and socket joints, and the holding means is shown in the form of abutting surfaces of the brake shoe and the opposing interior surface of the recess of the branch. In this embodiment, brake having mirror image branches, one 123 of which is shown in detail, is

formed with shoe retaining recesses 136 formed at their leading ends. Recesses 136, in turn, are formed with socket recesses 136 at the pivot points and with sufficient space 137 to permit brake shoe pivoting as hereinbefore described. The brake shoes 138, one of which is shown, are formed with hemispherical protuberances 139 and 139' on either side thereof for cooperation with sockets 136, and form the ball portion of the present ball and socket joints. Shoes 138, in similar manner to shoes 38 and 38' of the previous embodiment, are formed with braking surfaces of complementary arcuity to the surface of the rotating spindle member with which they cooperate in a braking of the spindle blade to a stop. Further, shoes 138 are formed with a rear surface 123 opposite their braking surfaces for abutting contact with an opposing and facing surface 123' formed at and defining the interior rear wall of recesses 136. Such cooperating surfaces for abutment form the holding means of the brake of this embodiment. This brake operates in similar manner to that of the previously described embodiment. Replacement of brake shoes is made simple, according to the invention. In order to provide a systematic method and a minimum of time expended both in brake shoe replacement and in machine down time, it is recommended that a periodic schedule for brake shoe re placement be devised such as every six 'or so months. With the machine stopped and the brakes in a fully released position, such as in FIGS. 2, 4 and 6, the operator can quickly scan the brake shoes at their pivot line PC to see which shoes need replacement; for those that do, their entire brakes are removed from their associated spindle assemblies and brakes with unwom shoes are immediately placed thereon. Then the removed brakes are taken to a convenient place, and the worn shoes removed, such as by removal of pivot pins of the first embodiment or a snapping of the balls out of their sockets of the second embodiment described above, to be replaced by unworn shoes. lt will be noted that one should have on hand an adequate supply of additional brakes to pursue this recommended procedure. Once done, these additional shoes with replacement, unworn shoes are available for use at the next periodic inspection.

ADVANTAGES OF THE INVENTION Brake shoes of the present invention provide the advantages of much greater useful lifetimes than brakes of the prior art because, upon application of the pres ent brakes, the full'braking surfaces of the shoes are im mediately applied to the rotating spindle member and thus abrasion and the braking force is evenly distributed over such entire surfaces, rather than at the very small leading braking surfaces as in prior art brakes. In order that this may occur, the present brake shoes are pivotally articulated to the brake branches.

A further advantage of the present invention is the great economies provided not only by extending the useful lifetimes of the brakes before shoe replacements are required, but also in the fact that one replaces but 7 the brake shoes themselves and may reuse indefinitely the rest of the brakes.

Having thus described preferred embodiments of the invention, their advantages of usage and operation, one

skilled in the art based upon the principles here taught may immediately think of variations which fall within the present concept and claims.

We claim:

1. In a bifurcate branched, elastically deformable spindle brake adapted for pivoting on a spindle assembly between a position of disengagement from and a position of holding engagement with a rotatable spindle member thereof, the improvement comprising:

brake shoes pivotally articulated with the respective branches of said brake for movement between and into said positions, formed with braking surfaces of complementary arcuity to said member for braking engagement therewith and extending toward said member beyond the adjacent periphery of their associated branches.

2. The improvement as in claim 1, wherein the separation of said branches along the line between the pivot points of shoe articulation is greater than the diameter of said member.

3. The improvement as in claim 1, wherein said shoes are pivotally articulated by means of detachable pivot pins.

4. The improvement as in claim 1, wherein said shoes are pivotally articulated by means of detachable ball and socket joints.

5. The improvement as in claim 1, wherein said pivot points are located on a line which at the position of holding engagement is over center of said member.

6. The improvement as in claim 5, wherein holding means is provided at least in part on said brake for retaining said brake in said position of holding engagement.

7. The improvement as in claim 6, wherein said holding means comprises opposing abutment surfaces at the apex of said branches and on said spindle member.

8. The improvement as in claim 6, wherein said holding means comprises opposing abutment surfaces on said shoes and on the shoe-receiving recesses of said branches associated therewith. 

1. In a bifurcate branched, elastically deformable spindle brake adapted for pivoting on a spindle assembly between a position of disengagement from and a position of holding engagement with a rotatable spindle member thereof, the improvement comprising: brake shoes pivotally articulated with the respective branches of said brake for movement between and into said positions, formed with braking surfaces of complementary arcuity to said member for braking engagement therewith and extending toward said member beyond the adjacent periphery of their associated branches.
 2. The improvement as in claim 1, wherein the separation of said branches along the line between the pivot points of shoe articulation is greater than the diameter of said member.
 3. The improvement as in claim 1, wherein said shoes are pivotally articulated by means of detachable pivot pins.
 4. The improvement as in claim 1, wherein said shoes are pivotally articulated by means of detachable ball and socket joints.
 5. The improvement as in claim 1, wherein said pivot points are located on a line which at the position of holding engagement is over center of said member.
 6. The improvement as in claim 5, wherein holding means is provided at least in part on said brake for retaining said brake in said position of holding engagement.
 7. The improvement as in claim 6, wherein said holding means comprises opposing abutment surfaces at the apex of said branches and on said spindle member.
 8. The improvement as in claim 6, wherein said holding means comprises opposing abutment surfaces on said shoes and on the shoe-receiving recesses of said branches associated therewith. 